Cone element acting as a clutch in a K0 installation space

ABSTRACT

A hybrid module for a vehicle arranged in a drivetrain between a drive unit, particularly an internal combustion engine, and an output, wherein an electric machine is provided, a rotor of the electric machine is connected to the output, and a clutch is provided between the drive unit and the electric machine, characterized in that the clutch is formed as a cone clutch.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a U.S. national stage of Application No. PCT/EP2019/081462 filedNov. 15, 2019. Priority is claimed on German Application No. DE 10 2018219 676.1 filed Nov. 16, 2018 the content of which is incorporatedherein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The disclosure is directed to a hybrid module comprising an internalcombustion engine and an electric machine, wherein a disconnect clutch,also known as K0, is provided between the internal combustion engine andthe electric machine.

2. Description of Related Art

Hybrid modules with a K0 are known from the prior art. The K0 requiresextensive additional installation space, which has an adverse effect onvehicle design. Further, the constructions put forth as solutions arerelatively complex and lead to extensive manufacturing expenditure.

SUMMARY OF THE INVENTION

It is an object of one aspect of the invention to provide a hybridmodule that requires less installation space, is less complex toconstruct, and/or is more easily producible compared with the prior art.

According to one aspect of the invention, a hybrid module for a vehicle,which is arranged in a drivetrain between a drive unit, particularly aninternal combustion engine, and an output, wherein an electric machineis provided, wherein a rotor of the electric machine is connected to theoutput, and wherein a clutch is provided between the drive unit and theelectric machine, is characterized in that the clutch is formed as acone clutch.

Embodiment forms of a hybrid module are characterized in that atorsional damper is likewise arranged between the drive unit and theelectric machine upstream and/or downstream of the clutch.

Hybrid modules according to embodiment forms are characterized in thatthe cone clutch is operatively connected on the driven side to a torqueconverter.

Embodiment forms of a hybrid module are characterized in that the coneclutch has only one friction surface.

Hybrid modules according to embodiment forms are characterized in thatthe cone clutch has at least one outer friction ring (ARR) and oneintermediate friction ring (ZRR), and the outer friction ring (ARR) isconnected to the rotor.

Further embodiment forms of a hybrid module are characterized in thatthe outer friction ring (ARR) is formed integrally with a rotor carrierof the rotor.

Hybrid modules according to preferred embodiment forms are characterizedin that a connection plate is provided on the driving side, and in thatthe intermediate friction ring (ZRR) is connected to the connectionplate by positive engagement in circumferential direction and ismoveable axially with respect to the connection plate.

Embodiment forms of a hybrid module are characterized in that the coneclutch has an inner friction ring (IRR), and in that the outer frictionring (ARR) and the inner friction ring (IRR) are arranged so as to befixed with respect to rotation relative to one another.

Hybrid modules according to embodiment forms are characterized in thatthe intermediate friction ring (ZRR) is formed in a segmented manner.

Embodiment forms of a hybrid module are characterized in that the coneclutch is formed as a normally open type.

Hybrid modules in embodiment forms are characterized in that the coneclutch is formed with at least one inserted friction lining that is notfixedly connected to another component part of the cone clutch.

Embodiment forms of a hybrid module are characterized in that the coneclutch can be actuated via a piston, and in that the piston is formedintegrally with the inner friction ring (IRR).

Embodiment forms of a hybrid module are characterized in that the conein a normally open type cone clutch tapers in direction of pistonactuation, and in that the cone in a normally closed type cone clutchtapers opposite the direction of piston actuation.

Hybrid modules according to embodiment forms are characterized in thatan oil baffle is provided at the cone clutch.

Embodiment forms of a hybrid module are characterized in that, fordirecting oil, a portion of the oil flow is guided through the open coneclutch, and this portion of the oil flow is interrupted when the coneclutch is actuated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an installation space with K0 as wet multiple disk clutch NO;

FIG. 2 is a construction of cone K0 with left-handed cone as NO;

FIG. 3 is a construction of cone K0 with left-handed cone as NO—cupspring;

FIG. 4 is a construction of cone K0 with left-handed cone as NC;

FIG. 5 is a construction of cone K0 with left-handed cone as NC—cupspring;

FIG. 6 is a construction of cone K0 with right-handed cone as NO;

FIG. 7 is a construction of cone K0 with right-handed cone as NO—ARRplate design;

FIG. 8 is a construction of cone K0 with right-handed cone as NO withonly one friction surface—minimal design without compensation space;

FIG. 9 is a construction of cone K0 with right-handed cone as NC;

FIG. 10 is a construction of cone K0 with left-handed cone as NO withonly one friction surface—minimal design without compensation space; and

FIG. 11 is a construction of cone K0 with right-handed cone as NO—ZRRconnected to torsional damper.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

FIG. 1 shows the construction of a wet multiple disk clutch as K0, whichrepresents the prior art. The inner disk carrier (ILT) 4 is connected tothe input part 1 via a rivet connection 3. The inner disks 5 areconnected to the ILT via a toothing 6 to be fixed with respect torotation but axially displaceable relative to it. The electric machine(EM) 10 is fastened with the rotor carrier 8 at the outer disk carrier(ALT) 9, and the latter is in turn fastened, shown here as weldconnections, to the converter cover 11.

Accordingly, in addition to the support function for the outer disks 7,the ALT also takes over the function of connecting the EM to theconverter cover and accordingly forms part of the rotor carrier. Themultiple disk clutch is constructed as a “normally open” (NO) system andmust be actively pressed via an actuation piston 12 to transmit torque.Owing to the normal force acting on the disks, there results via thecoefficient of friction μ at the linings a frictional force which, inaccordance with the strength of the contact force, makes possible thetransmission of a circumferential force, and therefore, depending on themean friction radius of the disks, the transmission of a torque.

The force at the piston results from oil pressure acting on the pistonsurface. The pressure space is formed between converter cover, piston,and hub 30. The pressure space is sealed radially outwardly via thepiston seal 13 and radially inwardly via a shaft sealing ring 20. Theoil supply is carried out via a controlled oil channel 19. When pressurebuilds up, the piston is displaced to the left against the force of thereturn spring 15 and presses on the right-hand outer disk. The lattermoves to the left via the toothing in the ALT and presses the laminationstack together. The lamination stack comprises an alternatingarrangement of outer disks and inner disks. The force is supported via athicker outer disk, known as the end disk 17, on a retaining ring (snapring) 18, which fits in a groove of the outer disk carrier. Since theALT is fixedly connected to the converter cover, the flux of force isclosed here. In order to minimize deformations of the component parts asfar as possible, a sufficient stiffness must be ensured in theconfiguration. The converter cover is welded to the hub and forms theoutput 2. In order to compensate for the influence of rotational speedon oil pressure in the piston chamber, which is constantly filled, acompensation space 21 is provided. The latter is formed by a sealingplate 16 and a seal 14. The compensation space is likewise supplied withoil via an oil channel. However, it is not acted upon by pressure.Further, the compensation space has only one seal radially outward onthe level of the piston seal. Overflow channels are provided radiallyinwardly for the displacement of the oil during piston actuation.Without oil pressure in the oil chamber, the return spring can press theoil back into the piston chamber through the oil channel 19.

FIG. 2 shows a construction of the K0 as NO type cone clutch withleft-handed cone. Compared to the multiple disk clutch in FIG. 1 , thepiston chamber and the compensation space 21 are interchanged.Therefore, the oil channels must also be interchanged. The pistonactuation is carried out to the right. The cone element is connected tothe input part 1 via a carrier plate 22 which is, e.g., riveted orwelded or fixed with respect to relative rotation is some other mannerand secured against axial displacement. This carrier plate has cutoutsin which the dogs 23 of the intermediate friction ring (ZRR) 24 engage.The torque is transmitted on the one hand and a radial and axialcompensation is made possible on the other hand via this dog plug-inconnection. For radial tolerance compensation, there must be playbetween the dogs and the cutouts in circumferential direction as well asradial direction.

As an alternative to a dog plug-in connection with play, a tolerancecompensation can also be carried out through the connection of the coneelement to a spring set (torsional damper) arranged upstream ordownstream. Depending on design, the torsional damper allows radial andaxial relative movement between the input part and output part byseparating the input part and output part via a resilient springelement. In order to minimize the imbalance as far as possible, it isadvisable to utilize the lighter side of the cone element (ZRR) and ofthe damper for tolerance compensation (no bearing).

When the piston 12 is actuated, the ZRR is clamped between the outerfriction ring (ARR) 26 and the inner friction ring (IRR) 27. The contactforce of the piston is multiplied via the cone angle so that the normalforce on the friction lining 25 is increased. In this way, with contactforce, mean friction radius and friction ratios (friction coefficient)remaining the same, a higher frictional force can be generated comparedwith a multiple disk clutch so that two friction surfaces are sufficientin this application. The larger actuation path in comparison with amultiple disk clutch is compensated by the smaller required quantity offriction surfaces and, in consequence thereof, smaller runningclearance. Limiting to two friction surfaces allows the toothing of theinner disk carrier and outer disk carrier to be omitted. A rotationallylocking connection 28 need merely be provided between the inner frictionring and outer friction ring with the possibility of axial displacement.

In this embodiment, the ARR is formed by a portion of the rotor carrier8. Alternatively, the outer friction ring can also be a separate partwhich is connected to the rotor carrier so as to be fixed with respectto rotation and axially secured relative to it.

In this instance, the IRR is part of the actuation piston 12. Aseparation spring between the inner friction ring and outer frictionring can be omitted by fixedly connecting the inner friction ring orouter friction ring to the piston. The separation and the return of thepiston is taken over by the return spring 15. As is shown, this returnspring 15 can be constructed as helical compression spring (SDF) set or,as is shown in FIG. 3 , may be constructed as a cup spring 34.

The element for preventing rotation 28 between the inner friction ringand outer friction ring is ensured in this case by a pin 28 orcomparable positive-locking element at the rotor carrier, which engagesin cutouts 29 at the inner friction ring and permits an axialdisplacement. Alternatively, the IRR may also be connected to the ARR orrotor carrier via:

-   -   tangential leaf springs;    -   a sliding spline (e.g., spline shaft toothing) between piston        and hub;    -   a cup spring (as return spring) which is mounted at the IRR and        at the hub or converter cover so as to prevent rotation        (positive engagement) and can accordingly transmit torque.

The hub is fixedly connected to the converter cover which is the drivenend. The rotor carrier is likewise fixedly connected to the convertercover. In this case, this connection is formed as rivet connection 36via an injection molded rivet at the converter cover. The rivet headscan also be completely recessed in the rotor carrier plate.

Oil pressure is introduced in the piston chamber 31 via the controlledoil channel 19 for piston actuation. Via the piston surface, this causesa force which works against the return spring 15, moves the piston and,therefore, the IRR to the right and clamps the ZRR between IRR and ARR.The piston chamber is formed by the sealing plate 32, the piston and thehub 30. In so doing, a static seal is used between sealing plate andhub, and two dynamic seals, piston seal 13 between sealing plate andpiston and between piston and hub 20.

As is shown, the compensation space is formed by a piston, hub, andconverter cover. A seal 14 seals the compensation space radiallyoutward. When a cup spring is used as return spring, the compensationspace can be formed between piston, hub, and cup spring. The seal 14must then be arranged between cup spring and piston on the same diameteras the piston seal.

In a variant with cup spring (FIG. 3 ) as return spring, the cooling oilflow can be guided radially outward through orifices at the innerdiameter of the cup spring 35 between converter cover and cup spring andcan therefore be guided directly to the cone. The cone element can alsobe utilized directly for oil control. For example, the cooling oil inthe open state of the clutch could be distributed in such a way that oneportion runs to the left through the cone and the other portion runs tothe right through a bore 44. In the closed state, the cone seals off theoil flow to the left and the oil is guided in its entirety to the rightthrough the bore 44.

This connection variant of the cone clutch offers the possibility of anadditional parallel frictional engagement, and therefore the increase inthe transmissible torque. When the stiffness of the sealing plate 32 iscorrespondingly configured, an additional frictional contact can becarried out between sealing plate 32 and carrier plate 22 after adetermined oil pressure is reached. To this end, the sealing plate 32must be connected to the hub so as to be fixed with respect to rotationrelative to it.

FIG. 4 shows the same construction of the cone clutch as a normallyclosed (NC) system. In this instance, the compensation space and thepressure space are again arranged comparable to FIG. 1 . The depictedspring set 37 does not serve in this instance for return but rather mustapply the maximum required closing force. As is shown in FIG. 5 , thisclosing spring can also be constructed as cup spring 39. An advantageherein consists in the supporting of the cup spring radially far insideat the sealing plate 16 of the compensation space. Therefore, thesealing plate need not be so robustly constructed. The sealing platecould even be omitted entirely if the cup spring 39 takes over thisfunction and, as has already been described, the sealing of thecompensation space 14 is carried out between cup spring and piston.

The flow of cooling oil to the cone can be carried out via an oil baffle38 (FIG. 5 ) mounted in or welded to the IRR.

FIG. 6 shows a constructional variant with a right-handed cone.Accordingly, compared with the left-handed cone, the actuation directionis reversed. The depicted variant shows a NO design. The pressure spaceis on the right and the compensation space is on the left.

During piston actuation, the piston is pressed with IRR to the left andclamps the ZRR between the IRR and ARR. The ARR 26 is supported axiallyvia a retaining ring 40, which is inserted in the rotor carrier 8. FIG.7 shows an alternative embodiment form of the ARR in the design of theplate. The rotor carrier is welded, for example, to a carrier plate 41,which in turn is riveted to the converter cover, for example. Thecarrier plate 41 comprises cutouts 29 in which dogs 28 of the ARR andthe IRR engage in a positive-locking manner and prevent rotation. Axialdisplaceability remains ensured. This plug-in connection should becarried out on the largest possible diameter, as has already beendescribed, in order to minimize the frictional forces which act againstan axial displacement under torque.

FIG. 8 shows a construction of the cone K0 with right-handed cone as NOdesign as in FIG. 6 with only one friction surface and withoutcompensation space and represents a minimal design for small torques.The torque introduced is no longer transmitted to the two paths ARR andIRR via a ZRR. There is no ZRR present in this case. The previous ZRRtakes over the function of the IRR 42. The piston in this case presseson the return spring, which is constructed as cup spring 34. Since acompensation space has been omitted in this example, the return springmust be strong enough that the oil pressure occurring in the pistonchamber at maximum speed does not cause the clutch to close. In thisinstance, in addition, the cup spring 34 takes over the function oftransmitting force from the piston to the IRR 42 and presents a levermechanism. The actuation force of the piston on the IRR is stepped downvia the leverage ratios. Therefore, it is advantageous when theconnection of the piston to the cup spring is carried out as farradially outward as possible. If the piston were connected on a diametergreater than that of the IRR, a multiplication would be carried out.However, this conflicts with a friction radius of the cone that is aslarge as possible.

Since the arrangement with only one friction surface in this embodimentexample does not permit a direct coupling between the piston and IRR,the separation of the friction surfaces in the no-pressure condition(NO) must be ensured by an additional spring 43. The ARR is supported atthe rotor carrier in this instance also via a retaining ring 40. Wheninstalled to the right, the retaining ring ensures that the clutch canbe mounted. The carrier plate 22 is mounted, e.g., riveted, at the inputpart 1 with pre-inserted separation spring 43. Cup spring, IRR and ARRare inserted on the transmission side and secured via the retaining ring40. The clutch is completed when the transmission is assembled at theengine in that the IRR 42 is inserted into the cutouts at the carrierplate 22. In so doing, the separation springs 43 ensure the runningclearance between IRR and ARR. In order to prevent drag torques in theopen state, it should be ensured that there is a second runningclearance between cup spring and IRR in the open state.

In this embodiment example, the rotor carrier is welded to the carrierplate 41, and the carrier plate is in turn welded to the convertercover.

FIG. 9 shows a construction of the cone K0 with right-handed cone as NC.

FIG. 10 shows a construction of the cone K0 with left-handed cone as NOwith only one friction surface. The compensation space can be formed inthis instance by the cup spring with additional sealing element or, asis shown in FIG. 8 , can be entirely omitted. An additional spring 43must likewise be used for the separation of the friction surfaces. Itmust be ensured during assembly that the separation spring ispre-mounted at the IRR and that the IRR is inserted into the cutouts atthe carrier plate 22 when the transmission is assembled at the enginesuch that the separation springs snap in at the carrier plate and pullthe IRR in direction of the carrier plate.

In FIG. 11 , the ZRR is held via the torsional damper and tolerancecompensation can be effected in both axial and radial direction by thespring set of the torsional damper. In further embodiment forms however,the torsional damper can also be arranged at another location.Alternatively, tolerance compensation can also be carried out by afurther torsional damper at another location.

Friction linings 25 are glued to the ZRR. Possibly, these frictionlinings may also simply be inserted only between ZRR and IRR and betweenZRR and ARR. However, the stiffness and strength must then besufficiently high to withstand tensile and compressive forces occurringduring slip (condition when closing with difference in speed between ZRRand inner friction ring and outer friction ring from the first frictioncontact until clutch is completely synchronized and closed).

As an alternative to a dog plug-in connection with play, a radialtolerance compensation (offset/angular error) can also be carried out bymeans of the connection of the cone element to an upstream or downstreamspring set (torsional damper). For reasons pertaining to design, thetorsional damper permits radial and axial relative movement betweeninput part and output part by separation of the input part and outputpart via a resilient spring element. In order to minimize imbalance, itis advisable to utilize the lighter side of the cone element (ZRR) andof the damper for tolerance compensation (no bearing). If this is notdesirable, the degree of freedom must be limited via appropriate bearingdesigns.

Omission of the toothing of the outer disk carrier and inner diskcarrier because this clutch makes do with only two friction surfaces andtherefore with only two torque paths. The coupling of the inner frictionring and outer friction ring is carried out by:

-   -   a positive engagement between rotor carrier and IRR which        constitutes a rotationally fixed connection with the possibility        of axial displacement—ideally on large diameter in order to        minimize frictional forces;    -   tangential leaf springs that can transmit torque in        circumferential direction pull direction and permit axial        displacement through deformation; accordingly, there are no        additional frictional forces in contact which counteract        actuation; the push direction can be additionally limited via        stops in order to protect the tangential leaf springs against        bending;    -   a positive engagement in the form of a sliding spline between        piston and hub; the hub is fixedly connected to the converter        cover, and the latter is fixedly connected to the rotor        carrier/ARR—disadvantage consists in the small connection        diameter and consequent high friction forces;    -   a cup spring (as return spring) which is fitted rotationally        fixedly (positive engagement) to the IRR and to the hub or        converter cover and can accordingly transmit torque.

ARR is part of the rotor carrier or is constructed as a separate partwhich is inserted in the rotor carrier as free from play as possible andsecured axially so as to be fixed with respect to rotation relative toit.

IRR is constructed as part of the actuation piston.

Additional parallel frictional contact between sealing plate and carrierplate in order to increase transmissible torque.

Cup spring (either return spring or closing spring indifferently) takesover sealing plate function.

Seal for compensation space is fitted to or inserted in cup spring.

Cup spring with bores at the inner diameter for conducting oil, coolingoil flow and for overflow during piston actuation.

Cone element is used for controlling or guiding the cooling oil flow.Cone open corresponds with line open and cone closed corresponds withline sealed.

Cup spring takes over function of a lever for transmitting force fromthe piston to the IRR as is shown in FIG. 8 . Different reductions ormultiplications can be employed depending upon the position of the forceapplication points.

Separation spring is mounted in the carrier plate, for example, whenonly one friction surface is formed.

Intermediate friction ring is not formed as closed ring but rather as asegmented ring in order to compensate for tolerances.

Friction linings are not glued on but only inserted. The facing cannotcreep out owing to the conical shape. This has the advantage thatadhesive work can be omitted. However, the following must be taken intoaccount in such embodiment forms:

-   -   The friction lining must be stiff enough so that it does not        crease on contact.    -   The friction lining must have sufficient strength so as not to        tear.    -   The drag torque of the clutch in the open state could increase        through contact of the friction lining between outer friction        ring and inner friction ring.

Minimum construction for small torques cone clutch with only onefriction surface FIGS. 8 and 10 .

The invention is not limited to the described embodiments. As statedabove, only individual features may also be provided or various featuresfrom different examples may be combined.

Thus, while there have shown and described and pointed out fundamentalnovel features of the invention as applied to a preferred embodimentthereof, it will be understood that various omissions and substitutionsand changes in the form and details of the devices illustrated, and intheir operation, may be made by those skilled in the art withoutdeparting from the spirit of the invention. For example, it is expresslyintended that all combinations of those elements and/or method stepswhich perform substantially the same function in substantially the sameway to achieve the same results are within the scope of the invention.Moreover, it should be recognized that structures and/or elements and/ormethod steps shown and/or described in connection with any disclosedform or embodiment of the invention may be incorporated in any otherdisclosed or described or suggested form or embodiment as a generalmatter of design choice. It is the intention, therefore, to be limitedonly as indicated by the scope of the claims appended hereto.

The invention claimed is:
 1. A hybrid module for a vehicle arranged in adrivetrain between a drive unit and an output, comprising: an electricmachine; a rotor of the electric machine is connected to the output, anda clutch is provided between the drive unit and the electric machine,wherein the clutch is a cone clutch, wherein the cone clutch comprises:at least one outer friction ring connected to the rotor; and oneintermediate friction ring formed in a segmented manner.
 2. The hybridmodule according to claim 1, wherein a torsional damper is arrangedbetween the drive unit and the electric machine upstream or downstreamof the clutch.
 3. The hybrid module according to claim 1, wherein thecone clutch is operatively connected on a driven side to a torqueconverter.
 4. The hybrid module according to claim 1, wherein the coneclutch has only one friction surface.
 5. The hybrid module according toclaim 1, wherein the outer friction ring is integrally formed with arotor carrier of the rotor.
 6. The hybrid module according to claim 1,further comprising: a connection plate provided on a driving side, andwherein the intermediate friction ring is connected to the connectionplate by positive engagement in circumferential direction and is axiallymoveable relative to the connection plate.
 7. A hybrid module for avehicle arranged in a drivetrain between a drive unit and an output,comprising: an electric machine; a rotor of the electric machine isconnected to the output, and a clutch is provided between the drive unitand the electric machine, wherein the clutch is a cone clutch, whereinthe cone clutch comprises: at least one outer friction ring connected tothe rotor; and one intermediate friction ring; an inner friction ring;and wherein the outer friction ring and the inner friction ring arearranged to be fixed with respect to rotation relative to one another.8. The hybrid module according to claim 7, wherein the intermediatefriction ring is formed in a segmented manner.
 9. The hybrid moduleaccording to claim 1, wherein the cone clutch is formed as normallyopen.
 10. The hybrid module according to claim 1, wherein the coneclutch is formed with at least one inserted friction lining that is notfixedly connected to another component part of the cone clutch.
 11. Thehybrid module according to claim 7, further comprising: a piston formedintegrally with the inner friction ring and configured to actuate thecone clutch.
 12. The hybrid module according to claim 1, for a normallyopen type cone clutch, the cone clutch tapers in direction of pistonactuation, and for a normally closed type cone clutch, the cone clutchtapers opposite the direction of piston actuation.
 13. The hybrid moduleaccording to claim 1, further comprising an oil baffle provided at thecone clutch.
 14. The hybrid module according to claim 1, wherein, fordirecting oil, a portion of an oil flow is guided through the open coneclutch, and the portion of the oil flow is interrupted when the coneclutch is actuated.
 15. The hybrid module according to claim 1, whereinthe drive unit is an internal combustion engine.